Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2019	Apr. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (17,311)	$ (10,006)
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on investments	254	(110)
Other comprehensive income (loss), net of tax	254	(110)
Comprehensive loss	$ (17,057)	$ (10,116)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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